diff --git a/Jellyfin.Plugin.SmartPlaylist/Lisp/Interpreter.cs b/Jellyfin.Plugin.SmartPlaylist/Lisp/Interpreter.cs
index b9db4d5..495c46a 100644
--- a/Jellyfin.Plugin.SmartPlaylist/Lisp/Interpreter.cs
+++ b/Jellyfin.Plugin.SmartPlaylist/Lisp/Interpreter.cs
@@ -188,7 +188,20 @@ namespace Jellyfin.Plugin.SmartPlaylist.Lisp {
             if (mi == null) {
                 throw new ApplicationException($"{o.Value()} has not method {s.Value()}");
             }
-            return Object.FromBase(mi.Invoke(o.Value(), (object?[]?) l.ToList().ToArray()));
+            object?[]? l_ = l.ToList().Select<Expression, object?>(x => {
+                switch (x) {
+                    case Integer s:
+                        return s.Value();
+                    case Boolean b:
+                        return b.Value();
+                    case Object o:
+                        return o.Value();
+                    case Cons c:
+                        return c.ToList().ToList();
+                }
+                return null;
+            }).ToArray();
+            return Object.FromBase(mi.Invoke(o.Value(), l_));
         }
     }